Emitter apparatus

ABSTRACT

A gas fired infrared radiation emitter that contains a frame, a screen assembly attached to the frame, and a device for locking the screen assembly to the frame. The screen assembly contains a support rod structure and at least four attachment rings attached to a screen. Each of the attachment rings is contiguous with a portion of the screen and, at the point at which each such attachment ring is contiguous with the screen, forms a screen contact point. The distance between any one screen contact point and the closest adjacent screen contact point does not exceed 75 millimeters.

CROSS-REFERENCE TO RELATED PATENT APPLICATION

This patent application claims priority based upon applicants'provisional patent application 60/719,481, filed on Sep. 22, 2005.

FIELD OF THE INVENTION

A gas fired infrared radiation emitter with improved screen life,improved energy efficiency and improved, and improved durability.

BACKGROUND OF THE INVENTION

U.S. Pat. No. 6,007,329, the entire disclosure of which is herebyincorporated by reference into this specification, described and claimeda novel gas fired infrared radiation emitter. U.S. Pat. No. 6,514,071improved upon the emitter with design aspects aimed at improvingdurability. U.S. Pat. No. 6,514,071, the entire disclosure of which ishereby incorporated by reference into this specification, describes andclaims: “A gas-fired infrared radiation emitter, comprising a frame, ascreen removably attached to said frame, and means for releasablylocking said screen to said frame, wherein said frame is comprised of afirst side, a second side, a first end, and a second end, and wherein:(a) said first side of said frame is integrally connected to a firstreceptacle, a second receptacle, and a third receptacle; (b) said secondside of said frame is integrally connected to a fourth receptacle, afifth receptacle, and a sixth receptacle; (c) said first end of saidframe is integrally connected to a first support, and said second end ofsaid frame is integrally connected to a second support, wherein saidscreen is contiguous with said first support and said second support;(d) said means for releasably locking said screen to said frame iscomprised of a first bar removably disposed within said first receptacleand said fourth receptacle, a second bar removably disposed within saidsecond receptacle and said fifth receptacle, and a third bar removablydisposed within said third receptacle and said sixth receptacle, whereineach of said first bar, said second bar, and said third bar is disposedless than about 0.2 inches from said screen; (e) said emitter furthercomprises means for allowing movement of said first bar, said secondbar, and said third bar towards one of said first side and said secondside for at least about 0.15 inches; (f) said emitter further comprisesmeans for limiting the movement of said first bar, said second bar, andsaid third bar towards one of said first side and said second side; and(g) said emitter further comprises a fourth bar extending between saidfirst end and said second end, wherein said fourth bar is removablyconnected to said first bar, said second bar, and said third bar . . .wherein each of said first receptacle, said second receptacle, saidthird receptacle, said fourth receptacle, said fifth receptacle, andsaid sixth receptacle extend through said screen . . . . wherein each ofsaid first receptacle, said second receptacle, said third receptacle,said fourth receptacle, said fifth receptacle, and said sixth receptacleis comprised of an orifice . . . further comprising a third supportintegrally connected to said first end of said frame . . . furthercomprising a fourth support integrally connected to said second end ofsaid frame . . . wherein said screen is contiguous with said thirdsupport and said fourth support . . . further comprising a seventhreceptacle integrally connected to said first end of said emitter . . .further comprising an eighth receptacle integrally connected to saidsecond end of said emitter . . . wherein said fourth bar is removablydisposed within said seventh receptacle and said eighth receptacle . . .further comprising means for allowing movement of said fourth bar for atleast about 0.15 inches . . . comprising first means for limiting themovement of said fourth bar . . . comprising second means for limitingthe movement of said fourth bar . . . further comprising a back body . .. further comprising a distributor . . . wherein each of said firstsupport, said second support, said third support, and said fourthsupport has a height of from about 0.2 to about 0.6 inches . . . whereinsaid orifice is a slotted orifice . . . wherein said emitter furthercomprises a multiplicity of end stops connected to said first bar, saidsecond bar, said third bar, and said fourth bar . . . wherein each ofsaid first bar, said second bar, said third bar, and said fourth bar iscomprised of an orifice.”

The gas fired radiation emitter of U.S. Pat. No. 6,514,071 has met witha reasonable degree of commercial success. However, during prolongedhigh-temperature usage of such emitter, the screens often sag andultimately split, thereby causing damage to the substrates being driedas well as adversely affecting the energy efficiency and operation ofthe emitter. Additionally, an improved screen design provides animproved screen replacement process reducing some of the cumbersomesteps in the screen replacement process of U.S. Pat. No. 6,514,071.

It is an object of this invention to provide an improved gas firedinfrared radiation emitter that is more durable than the emitters ofU.S. Pat. Nos. 6,007,329 and 6,514,071.

It is an object of this invention to provide an improved gas firedinfrared radiation emitter that is more energy efficient than theemitters of U.S. Pat. Nos. 6,007,329 and 6,514,071.

It is an object of this invention to provide an improved gas firedinfrared radiation emitter with a screen that has a longer screen lifethan the emitters of U.S. Pat. Nos. 6,007,329 and 6,514,071.

It is an object of this invention to provide an improved gas firedinfrared radiation emitter with a screen with increased flatnessstability than the emitters of U.S. Pat. Nos. 6,007,329 and 6,514,071.

It is an object of this invention to provide an improved gas firedinfrared radiation emitter with a screen with reduced inward saggingtoward the emitter surface than the emitters of U.S. Pat. Nos. 6,007,329and 6,514,071.

It is an object of this invention to provide an improved gas firedinfrared radiation emitter with a screen with reduced sagging outwardfrom the emitter surface than the emitters of U.S. Pat. Nos. 6,007,329and 6,514,071.

It is an object of this invention to provide an improved gas firedinfrared radiation emitter with a simplified screen replacement processthan the emitters of U.S. Pat. Nos. 6,007,329 and 6,514,071. The reducedtime required in replacing the screen reduces the down-time of thedrying equipment employing this apparatus.

SUMMARY OF THE INVENTION

In accordance with this invention, there is provided a gas firedinfrared radiation emitter that contains a frame, a screen assemblyattached to the frame, and a device for locking the screen assembly tothe frame. The screen assembly contains a support rod structure and atleast four attachment rings attached to a screen. Each of the attachmentrings is contiguous with a portion of the screen and, at the point atwhich each such attachment ring is contiguous with the screen, forms ascreen contact point. The distance between any one screen contact pointand the closest adjacent screen contact point does not exceed 75millimeters.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described by reference to the following drawings,in which like numerals refer to like elements, and in which:

FIG. 1 depicts one preferred emitter of this invention;

FIG. 2 depicts the frame and backbody of the emitter of FIG. 1 with thescreen assembly removed;

FIG. 3 depicts one preferred embodiment of a screen assembly of theemitter of FIG. 1;

FIG. 4 is an exploded view of the emitter of FIG. 1 with the screenassembly separated from the backbody;

FIGS. 5A and 5B are partial perspective views of a one embodiment of avertically extending mounting bracket of the emitter of FIG. 1;

FIG. 6 is a partial perspective view of one embodiment of a screensupport of the emitter of FIG. 1;

FIG. 7 is a side view of the emitter of FIG. 1; and

FIG. 8 is a partial schematic view of the device depicted in FIG. 2;

FIG. 9 is a top view of the support rod assembly of the screen assemblyof FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

U.S. Pat. No. 6,514,071 describes an emitter where the “frame” does notrequire the welding of any fixtures. Instead, when the frame is made,the “retaining bar holders” are bent up and thus are an integral part ofthe assembly. The entire disclosure of this United States patent ishereby incorporated by reference into this specification.

FIG. 1 depicts one preferred emitter of this invention, a gas-firedinfrared radiation emitter 10. Emitter 10 is comprised of a back body12. This back body 12 is provided with a distributor (not shown) fordistributing a fuel-oxygen containing gas mixture (not shown); and it issubstantially identical to the back body 28 depicted in FIG. 2 of U.S.Pat. No. 6,007,329 and FIG. 1 of U.S. Pat. No. 6,514,071.

Referring again to FIG. 1, the emitter 10 is further comprised of adistributor (not shown) that preferably is substantially identical tothe distributor 32 depicted in FIG. 2 of U.S. Pat. No. 6,007,329 andFIG. 1 of U.S. Pat. No. 6,514,071.

The emitter 10 also is comprised of a frame 16. In one embodiment, thisframe 16 differs from the frame 12 depicted in U.S. Pat. Nos. 6,007,329and 6,514,071. In another embodiment, a metal fiber mat (not shown) isthe radiating medium in the emitter. Reference may be had, e.g., toelement 34 of FIG. 2 of U.S. Pat. No. 6,007,329, which, in oneembodiment thereof, is a mat of sintered metal fibers with a thicknessof about 3.0 millimeters and a surface area of about 48 square inches.

Referring again to FIG. 1, the emitter 10 is further preferablycomprised of a screen assembly 70. This screen assembly, more fullydepicted in FIG. 3 and described below, preferably differs from thescreen assemblies described in U.S. Pat. Nos. 6,007,329 and 6,514,071.

Screen assembly 70, in one embodiment, is removably attached to frame 16and comprises a support rod structure, a plurality of attachment ringsand a screen.

FIG. 2 depicts the frame and backbody of the emitter of FIG. 1 with thescreen assembly removed. Referring to FIG. 2, it will be seen that frame16 is comprised of a first end 18, a second end 20, a first side 21, anda second side 24, and an upper surface 25/58/46/48.

Referring to FIG. 2, integrally connected to the first end 18 is a firstvertically extending mounting bracket 22. Preferably, the verticallyextending mounting bracket is bent up from the frame, however, thevertically extending mounting bracket 22 may be operatively connected bywelding or other appropriate means of adhesion known to those skilled inthe art. This vertically extending mounting bracket 22, as well asvertically extending mounting bracket 28, forms an angle with uppersurface 25 of frame 18 of from about 70 to about 90 degrees; and itpreferably has a height 26 of from about 8 millimeters to about 20millimeters and, more preferably, from about 10 millimeters to about 15millimeters. As will be apparent, the vertically extending mountingbracket 22 is adapted to engage the emitter screen assembly 70 (notshown in FIG. 2, see FIG. 1). The mounting bracket 22 is preferablyadapted to prevent the screen assembly 70 from moving longitudinally andtransversely.

Similarly, and again referring to FIG. 2, vertically extending mountingbrackets 30 and 32 form an angle with upper surface 58 of frame 18 offrom about 70 to about 90 degrees; and they preferably have a height 26of from about 8 millimeters to about 20 millimeters and, morepreferably, from about 10 millimeters to about 15 millimeters. As willbe apparent, vertically extending mounting brackets 30/32/22/28 areadapted to engage the emitter screen assembly 70 (not shown in FIG. 2,see FIG. 1). These mounting brackets 30/32/22/28 prevent the screenassembly 70 from moving longitudinally and transversely.

In the embodiment depicted in FIG. 2, there are two vertically extendingmounting brackets 22, 28 connected to the first end 18, and anadditional two such vertically extending mounting brackets 30, 32oppositely disposed and connected to the second end 20 of the frame 16.In another embodiment, not shown, only one such vertically extendingmounting bracket is connected to each of ends 18 and 20. In yet anotherembodiment (not shown), at least three such vertically extendingmounting brackets are connected to each of ends 18 and 20. In general,from about 1 to about 4 such vertically extending mounting brackets arepreferably disposed on each of ends 18 and 20. As it will be apparent tothose skilled in the art, the number of vertically extending mountingbrackets depends upon the length of the side 18,20, where a longer sidelength requires more supports. Vertically extending mounting brackets22/28/30/32 are more fully depicted in FIGS. 5A and 5B and described ingreater detail below.

In another embodiment (not shown), the vertically extending mountingbrackets may be disposed on sides 21 and 24. As will be apparent, thescreen supports would correspondingly be disposed on sides 18 and 20.

Referring again to FIG. 2, it will be seen that, in the preferredembodiment depicted, each of sides 21 and 24 has integrally connected toit a multiplicity of screen supports 34 and 36, and 40 and 42,respectively. Screen supports 34/36/40/42 are more fully depicted inFIG. 6 and described in greater detail below.

In one embodiment, depicted in FIG. 2, each of the secondary screensupports 34 and 36 forms an angle with upper surface 46 of side 21 offrom about 70 to about 100 degrees. Similarly, in this embodiment, eachof secondary screen supports 40 and 42 also forms an angle with uppersurface 48 of side 24 of from about 70 to about 100 degrees. Preferably,the screen supports are bent up from the frame, however, they may beoperatively connected by welding or other appropriate means of adhesionknown to those skilled in the art. Each screen support 34/36/40/42comprises a top surface 318/320/322/324 and an exterior surface310/312/314/316 of the screen supports 34/36/40/42. In some embodimentsof the screen assembly, where the edges of the screen are downwardlybent, the screen contacts exterior surfaces 310/312/314/316 of thescreen supports 34/36/40/42.

Referring again to FIG. 2, the supports 22 and 28 limit the extent towhich screen assembly 70 (not shown in FIG. 2, see FIG. 1) can move inone direction, and supports 30 and 32 limit the extent to which thescreen assembly 70 can move in another direction.

Referring again to FIG. 2, and in the preferred embodiment depictedtherein, it will be seen that each of the vertically extending mountingbrackets 22/28/30/32 is comprised of an orifice 52 adapted to receive alocking device 54. In the embodiment depicted, the locking device 54 isa cotter pin. As will be apparent, other locking devices and/or lockingassemblies also may be used. In using the present invention, it will beapparent that screen assembly 70 is secured by disposing lockingmechanism 54, e.g. a cotter pin, in orifice 52 in the direction of arrow60.

In one embodiment, when the frame 16 is made, the screen supports34/36/40/42 are preferably bent up and are integrally attached to theframe 16, thereby obviating the need to weld such holders to the frame.Similarly, vertically extending mounting brackets 22/28/30/32 arepreferably bent up and are integrally attached to the frame 16, therebyobviating the need to weld such holders to the frame.

FIG. 3 depicts screen assembly 70. Screen 200 is substantially identicalin structure and function to the screen 14 illustrated in FIGS. 1 and 2of U.S. Pat. No. 6,007,329 and screen 70 in FIG. 3 of U.S. Pat. No.6,514,071. Referring again to FIG. 3, and in the preferred embodimentdepicted therein, the screen 200 preferably has a wire thickness of fromabout 1 to about 3 millimeters and, more preferably, about 1.5millimeters. In a preferred embodiment (not depicted) the screen 200 isdownwardly along first edge 302, second edge 304, third edge 306 andfourth edge 308. Referring again to FIGS. 2 and 3, when in use,downwardly bent edges 302/304/306/308 are disposed adjacent to theexterior surface 310/312/314/316 of the corresponding screen supports34/36/40/42. Without wishing to be bound by any particular theory,applicant believes that bending the edges of the screen inward towardthe direction of the primary radiating surface further increases theemitter efficiency. Applicant believes that extending the flatdimensions of the screen by about 30 millimeters into the length and thewidth and then bending the 4 edges of the screen by, for example 90degrees and to a distance of about 15 millimeters, would increase thetotal screen surface area by from about 15% to about 35% (subject to theflat screen size). As will be apparent to those skilled in the art, onemajor benefit of using a screen is to increase efficiency of the emitterapparatus. Applicant believes that the screen becomes a secondaryinfrared radiator that obtains its energy not only from absorbinginfrared radiation emitted from the primary radiator, but also byabsorbing energy contained in the flue gases (which energy otherwisewould be wasted).

Referring again to FIG. 3, screen 200 as depicted has a length 208 offrom about two inches to about twenty inches and a width 210 of fromabout one inch to about ten inches. In a preferred embodiment, screen200 has a length 208 of about eight inches and a width 210 of about sixinches.

In another embodiment (not shown), the screen size approximately equalsthe outside dimensions of frame 16. In such embodiment, screen 200 couldbe notched at each corner to allow for the protrusion of the verticallyextending mounting bracket. Put more simply, the screen shape wouldapproximate a rectangle with its four corners missing. In suchembodiment, the length of each side of the screen would beproportionately reduced by a distance not exceeding 25% of the length ofthe side.

Referring again to FIG. 3, screen 200 has an open space area of fromabout 30 per cent to about 70 per cent of the total surface area of thescreen 200, preferably from about 45 to about 55 per cent. As used inthis specification, open space area means that portion of the screen 200that comprises a void between the wire mesh members, or, in thevernacular, “the holes in the screen.”

Referring again to FIG. 3, and to the preferred embodiment depictedtherein, screen assembly 70 further comprises support rod structure 212and attachment rings 202. As will be apparent, the length and width ofthe support rod structure 212 is appropriately proportioned according tothe size of screen 200. In the embodiment depicted, Support rodstructure 212 comprises a first outer longitudinal support rod 214, asecond outer longitudinal support rod 204, a first inner longitudinalsupport rod 405, a second inner longitudinal support rod 409, andtransverse support rods 411/413/415/417/419. The inner longitudinalsupport rods 405 and 409 and the transverse support rods411/413/415/417/419 together form a substantially H-shaped connectingportion 206. Each outer longitudinal support rod has a first securingpoint 216 and a second securing point 218 that is disposed in avertically extending mounting bracket, e.g. 22/28/30/32, (not shown inFIG. 3, but see FIG. 2) while in use.

In one preferred embodiment, each of the outer longitudinal support rods204 and 214 are substantially parallel to each other. In anotherembodiment, each of the inner longitudinal support rods 405 and 409 aresubstantially parallel to each other. In one aspect of this embodiment,the transverse support rods 411, and/or 413, and/or 415, and/or 417,and/or 419 are substantially perpendicular to one or more of suchlongitudinal support rods, forming an angle therebetween of from about85 to about 95 degrees and, more preferably, from about 88 to about 92degrees.

As used herein, the term “substantially parallel” refers to structureswhose horizontal axes form an angle of from about 0 to about 5 degreeswith regard to each other.

More particularly described, the support rod structure may beconstructed such that the unsupported distance of the contact points onthe screen portion to the closest adjacent contact point is preferablynot greater than about 75 millimeters and, more preferably, not greaterthan about 60 millimeters. In one embodiment, the distance betweenadjacent support points is from about 15 to about 20 millimeters.

Referring to FIG. 4, and to the preferred embodiment depicted therein,it will be seen that a multiplicity of attachment rings 202 areconnected to the screen 200 and are contiguous with a portion of suchscreen. Where such contiguity exists, it forms contact points 203, 205,207, 209, 211, 213,215, 217, 219, 221 and 223 Each contact point will beadjacent to two or more contact points. Thus, and referring to FIG. 4,contact point 203 is adjacent to contact point 205 and 207. As usedherein, the term “adjacent” refers to contact points that areencountered when one sweeps 360 degrees around a first contact point todetermine the closest adjacent contact points. Thus, and referring toFIG. 4, the closest adjacent contact points about the periphery ofcontact point 203 are contact points 205, 207, 209, and 211. The maximumdistance between contact point 203 and such contact points 205, 207,209, and 211 does not exceed 75 millimeters and, more preferably, 60millimeters. In one aspect, such maximum distance is between 15 and 20millimeters.

Put another way, and referring to the surface of the screen 200, thereis no attachment ring that is more than 75 millimeters away from anadjacent attachment ring when one looks around the periphery of thereference attachment ring.

Referring to FIG. 9, and in the preferred embodiment depicted therein,the support rod structure may be formed from a first member 204, asecond member 409, a third member 419, a fourth member 405, and a fifthmember 214 Referring again to FIG. 9, first member 204 and fifth member214 preferably have a length 970 of from about 25 per cent less than toabout 25 per cent greater than the length 208 of screen 200, in oneembodiment, about six inches. In one embodiment, length 970 comprisesfrom about 1.9 to about 25 inches. Referring again to FIG. 9, secondmember 409 and fourth member 405 have a length 971 of from about 5 percent less than to about 25 per cent greater than the length 208 ofscreen 200, in one embodiment, about six inches. In one embodiment,length 970 is from about 1.9 to about 25 inches In one embodiment with ascreen size of 4 inches by 3 inches, said third member 419 has a length934 of about one inch. It is to be understood that the measurements ofmembers 204/409/419/405/214 may be proportioned as appropriate for thesize of screen 200.

In one preferred embodiment depicted in FIG. 9, fourth member 405 isbent at four points 928/920/918/926. At points 926 and 928 of from aboutone to about one and one-quarter inches from each end of the fourthmember, both points being equidistant from the midpoint 936 of thefourth member, said member is bent to form an angle 902 of from about 70to about 120 degrees, preferably about 90 degrees. At a point 918 and920 of from about one-eighth inch to about three-quarters inch from theclosest end of said fourth member, both points being equidistant fromthe midpoint 936 of said fourth member, said fourth member is bent toform an angle 906 of from about 70 to about 120 degrees, preferablyabout 90 degrees, to form a platforms 910 and 912 that may facilitateattachments 960 and 958 with said fifth member 214. Said third member419 is integrally attached to the midpoint 936 of said fourth member 405at point 966 by welding or other appropriate method known to thoseskilled in the art.

Similarly, again referring to FIG. 9, the second member 409 is attachedto the first member 204 and the third member 419 thus forming an “H”configuration. Second member 409 is bent at four points 922/924/932/930.At a point 930 and 932 of from about one to about one and one-quarterinches from the closest ends of the second member, both points beingequidistant from the midpoint 938 of the second member, said member isbent to form an angle 904 of from about 70 to about 120 degrees,preferably about 90 degrees.

Optionally, at a point 922 and 924 of from about one-eighth inch toabout three-quarters inch from the closest end of said second member,both points being equidistant from the midpoint 938 of said secondmember, said second member is bent at an angle 908 of from about 70 toabout 120 degrees, preferably about 90 degrees, to form a platforms 914and 916 that may facilitate integral attachment with said first member204 at points 962 and 964. Said third member 419 is integrally attachedto the midpoint 938 of said second member 409 at point 968.

In another embodiment (not shown), members 405 and 409 are not bent atpoints 922/924/930/932, but rather, cross over members 214 and 204respectively, extending a distance such that said member does notprotrude beyond the outside dimensions of frame 16. Said members may bewelded or otherwise integrally connected at such points where they meet.In another embodiment (not shown) said members may be notched andconnected according to the teachings of FIG. 4 of U.S. Pat. No.6,514,071 and the specification generally.

In one embodiment, ends 954, 956 of first member 204 are bent to form aradius of from about 45 degrees to about 330 degrees. The bends form afirst and second securing point of the first member. Similarly, ends 950and 952 of fifth member 214 are bent to form a radius of from about 45degrees to about 330 degrees. These bends form a third and fourthsecuring points of the second member. This bent configurationfacilitates an operative connection with the vertically extendingmounting brackets.

Referring again to FIG. 3, and in the preferred embodiment depictedtherein, the support rod structure 212 preferably has a diameter or wirethickness of from about 2 to about 10 millimeters and, more preferably,from about three millimeters to about 5 millimeters. In the embodimentdepicted, the support rod structure 212 comprises relatively flatmembers, however, it should be understood that these may be rounder(e.g. wire-shaped) without affecting functionality as long as securingpoints 216 and 218 (and their respective equivalents on otherlongitudinal support rods) are appropriately shaped for insertion in thevertically extending mounting brackets 22/28/30/32.

Referring again to FIG. 3, and in the preferred embodiment depictedtherein, substantially H-shaped connecting portion 206 may be formedfrom 3 members 220/224/222 integrally connected by welding or otheradhesion means known to one skilled in the art at points 226 and 228.Substantially H-shaped connecting portion 206 may be integrallyconnected to outer longitudinal support rods 214 and 204 by welding orother adhesion means known to one skilled in the art at points230/232/234/236. The substantially H-shaped connecting portion functionsto secure screen 200 to emitter frame 16 in a manner that allows forexpansion and contraction of the metals of rod structure 212 and screen200 while in use while preventing inward and outward sagging of screen200.

Referring again to FIG. 3, and in the preferred embodiment depictedtherein, attachment rings 202 secure support rod structure 212 to screen200. Attachment rings 202 comprise a section of wire formed into a smallloop with a diameter of the loop from about one millimeter to about 5millimeters, preferably from about 1 millimeter to about 3 millimeters.In other embodiments, one may alternatively use any appropriatefastening means known to one skilled in the art. Attachment rings 202function to secure support rod structure 212 to screen 200 in a mannerthat allows for expansion and contraction of the metals of rod structure212 and screen 200 while in use while preventing inward and outwardsagging of screen 200. The “play” between the screen 200 and the supportrod structure 212 is from about one to about five millimeters,preferably from about one to about three millimeters, and mostpreferably about one millimeter. As used in the specification, the playmeans the maximum distance between the exterior surfaces of the screen200 and the support rod structure 212 when connected by the attachmentrings 202. As depicted in FIGS. 1,3,4 and 9, a plurality of saidattachment rings 202 are disposed about the support rod structure 212and are adapted to secure screen 200 to support rod structure 212.

In one embodiment (not depicted), the screen supports 34/36/40/42protrude through the screen 200. In order for the screen supports34/36/40/42 to protrude through the screen 200, two methods may be used.In one embodiment, slots are cut into the screen 200. In anotherembodiment, that portion of the screen 200 is simply cut away.

FIG. 4 is an exploded view of the emitter 10, with the screen assemblyseparated from the backbody and showing how such parts are fittedtogether. In one embodiment, screen assembly 70 is lowered in thedirection of arrows 404 toward backbody 16, fitted into second slot-typeopening 408 in vertically extending mounting brackets 22/28/30/32 andsecured by disposing locking mechanism 54 (e.g. a cotter pin) in orifice52 in the direction of arrow 60. In the embodiment depicted, cotter pins54 may then be bent downward 402 to secure the screen assembly 70 inplace in the vertically extending mounting brackets 22/28/30/32. In apreferred embodiment, cotter pins 54 have a diameter at least as thickas that of the wire mesh of screen 200. In one embodiment, the diameterof cotter pin 54 is from about 1 millimeter to about 3 millimeters.

FIGS. 5A and 5B are partial perspective views of one embodiment of avertically extending mounting bracket of the emitter of FIG. 1.Referring to FIGS. 5A and 5B, vertically extending mounting brackets,e.g. 22/28/30/32 (not shown in FIGS. 5A or 5B, see FIGS. 2 and 4), havea length 506 of from about 8 millimeters to about 20 millimeters and,more preferably, from about 10 millimeters to about 15 millimeters.Vertically extending mounting brackets, e.g. 22/28/30/32 (not shown inFIGS. 5A or 5B, see FIGS. 2 and 4), have a width 508 of from about 6millimeters to about 30 millimeters and, more preferably, from about 10millimeters to about 18 millimeters. In a preferred embodiment, aslot-type opening 408 in vertically extending mounting brackets22/28/30/32 (not shown in FIGS. 5A or 5B, see FIGS. 2 and 4) is disposedat a distance 502 of about 7 millimeters to about 14 millimeters and,preferably, about 10 millimeters from the surface of frame 16. In someembodiments (not shown) void 512 (see FIG. 5B) does not exist, that isto say that the bracket is a continuous member at this situs. In theembodiment depicted, orifice 52 comprises a hole and has a diameterappropriately sized to receive the locking mechanism 54 (not shown inFIGS. 5A or 5B, see FIGS. 2 and 4), which, in some embodiments is fromabout one to about three millimeters.

In another embodiment (not shown), the vertically extending mountingbrackets have rounded and/or flared out features (as opposed togeometric, angular and perpendicular alignments) forming angles of fromabout 30 to about 280 degrees with the frame. In some embodiments,orifice 408 has rounded or flared out features (as opposed to geometric,angular and perpendicular alignments) forming angles of from about 30 toabout 280 degrees with the vertically extending mounting bracket. In allembodiments, orifice 408 is appropriately sized to receive the rodsupport structure of the screen assembly.

FIG. 6 is a partial perspective view of one embodiment of a screensupport of the emitter of FIG. 1. Each of the screen supports 34, 36,40, and 42 (34, 36 and 40 are not shown in FIG. 6, see FIGS. 2 and 4)has a height 606 of from about 7 millimeters to about 14 millimeters,preferably about 10 millimeters. Each of the screen supports 34, 36, 40,and 42 (34, 36 and 40 are not shown in FIG. 6, see FIGS. 2 and 4) has awidth 604 of from about 8 millimeters to about 25 millimeters,preferably about 15 millimeters, and a depth 602 of from about 3millimeters to about 15 millimeters, preferably about 9 millimeters.Optionally, sloped surface 608 may be incorporated, or alternatively,there may be a fourth vertical wall (depicted by dashed line 612)forming the screen support. As will be apparent, the top surface 610 ofthe screen supports should be the same height at the bottom surface 510(depicted in FIG. 5B) of the slot-type opening of the verticallyextending mounting brackets.

Referring again to FIG. 6, each of the screen supports 34, 36, 40, and42 (34, 36 and 40 are not shown in FIG. 6, see FIGS. 2 and 4) iscomprised of the same material as frame 16 and integrally connectedthereto. As will be apparent to one skilled in the art, the materialsthat comprise frame 16, as well as all parts of emitter apparatus 10(not shown in FIG. 6, see FIG. 1), must be selected for structuralintegrity at high temperatures such as from about 1900 to about 2300degrees Fahrenheit. As known to those skilled in the art, loss ofstructural stability of the frame 16 can lead to leakage of the gas andair mixtures from either the back of the emitter apparatus (where thebackbody is joined to the frame) or the front of the emitter apparatus,where the primary radiating material is joined to the frame 16. Suchleakage can lead to “flashback” of the flame front from the primaryradiating material into the interior of emitter apparatus 10 (not shownin FIG. 6, see FIG. 1) and rapid failure.

FIG. 7 is a side view of the emitter of FIG. 1 and FIG. 8 is a partialschematic view of the screen assembly of FIG. 2. These figuresdemonstrate how screen assembly 200 is secured in the verticallyextending mounting brackets. In using the present invention andreferring to FIG. 7, first end 708 of screen assembly 70 is broughttoward end 18 of frame 16 and vertically extending mounting bracket 28in the direction of arrow 704 until securing point 218 is disposedwithin an orifice, e.g., slot-type opening 408. Then second end 710 ofscreen assembly 70 is then brought down toward end 20 of frame 16 in thedirection of arrow 706, rotating securing point 218 about a pivot aboutorifice 52 in the direction of arrow 702, until screen assembly 70 restson the top surface 712 of screen supports 34 and 36 and securing point216 is disposed within second orifice, e.g., slot-type opening 718 onvertically extending mounting bracket 32 of end 20 of frame 16.Referring to FIG. 8, outer longitudinal support rod 204 is disposed insecond orifice, e.g., slot-type opening 408 on vertically extendingmounting bracket 28. A locking mechanism, e.g. a cotter pin, (not shown)is optionally and additionally disposed in orifice 52.

Referring again to FIGS. 4, 5A, 5B, and 9, in one embodiment, a firstvertically extending mounting bracket 22 comprises a first orifice 408adapted to receive one of said first member 204 or said fifth member214, a second vertically extending mounting bracket 28 comprises asecond orifice 408 adapted to receive one of said first member 204 orsaid fifth member 214, a third vertically extending mounting bracket 30comprises a third orifice 408 adapted to receive one of said firstmember 204 or said fifth member 214, a fourth vertically extendingmounting bracket 32 comprises a fourth orifice 408 adapted to receiveone of said first member 204 or said fifth member 214. Thus, the meansfor releasably locking said screen assembly 70 to said frame 16comprises a first member 204 removably disposed within said firstorifice and said third orifice, a fifth member 214 removably disposedwithin said second orifice and said fourth orifice, and wherein saidfirst member 204 and said fifth member 214 are disposed from about 0.5to about 5.0 millimeters from said screen. Similarly, the means forallowing movement of said first member 204 and said fifth member 214towards one of said first end 18 of said frame or said second end 20 ofsaid frame comprises a first member 204 removably disposed within saidfirst orifice and said third orifice, a fifth member 214 removablydisposed within said second orifice and said fourth orifice, and whereinsaid first member 204 and said fifth member 214 are disposed from about0.5 to about 5.0 millimeters from said screen. In one embodiment, saidmeans for allowing movement of said first member 204 and said fifthmember 214 towards one of said first side 21 of said frame or saidsecond side 24 of said frame comprises said slot-shaped orifice.

Referring again to FIG. 4, in one embodiment, a first verticallyextending mounting bracket 22 comprises a fifth orifice 52 adapted toreceive a locking device 54, a second vertically extending mountingbracket 28 comprises a sixth orifice 52 adapted to receive a lockingdevice 54, a third vertically extending mounting bracket 30 comprises aseventh orifice 52 adapted to receive a locking device 54, and a fourthvertically extending mounting bracket 32 comprises an eighth orifice 52adapted to receive a locking device 54.

It will be apparent to those skilled in the art that there aresubstantial advantages to the instant assembly, when it is compared tothe assembly of U.S. Pat. Nos. 6,007,329 and 6,514,071, copies of whichare attached. The screen and vertically extending mounting brackets areintegrally connected to each other through loops that make thatconnection a “freely floating” connection. As will be apparent to thoseskilled in the art, the screen 70 can expand and contract freely withchanges in temperature while the vertically extending mounting bracket22/28/30/32 structure can also expand and contract independently. Theexpansion range fro the emitter apparatus is from about one to abouteight millimeters.

The shape of the screen support structure is designed to offer greaterform stability to the screen. The loosely attached attachment rings 202reduce inward sagging toward the emitter and the oddly shaped rodsreduce outward distortion away from the emitter. Sagging, both inwardsagging and outward sagging, is a function of screen 200 exposure totemperatures greater than 1900 degrees Fahrenheit and gravity actingupon the heated wire of the screen. For example, when the apparatus isinstalled facing downward, gravity will want to pull the screen shapeaway from the apparatus surface, and conversely, when the apparatus isinstalled facing upward, gravity will want to pull the hot screen wiredtoward the emitter surface. In either case, when the screen distorts toomuch into either direction, the life of the screen is shortened and theenergy efficiency of the apparatus is reduced. As known to those skilledin the art, there is a clearly established correlation between screendistance from the radiating material underneath and the efficiency.

Screen replacement time is shortened, thereby reducing the down-time ofdryers that use this infrared technology. For all existing technologies,the replacement of a screen involves numerous steps: each of the supportrods has to be disconnected from two brackets, the screen has to beremoved, a new screen must be held in place, new support brackets areinstalled, and new support brackets are locked into place. The presentinvention provides a novel design that greatly simplifies this process.In the process of the present invention, or in using the presentinvention, the screen assembly simplifies replacement wherein a lockingmechanism (a bent wire) is removed from each of the vertically extendingmounting brackets, the entire screen assembly is removed, a new screenassembly is placed into the brackets, and the brackets are locked.

The emitter of the present invention is unexpectedly substantiallysuperior to prior art emitters and substantially more durable. Testshave demonstrated that the emitter of the instant invention has a screenlife that is at least about 35% percent greater than the screen life ofthe emitter of U.S. Pat. No. 6,514,071, when tested in high temperaturedrying environments.

It is to be understood that the aforementioned description isillustrative only and that changes can be made in the apparatus, in theingredients and their proportions, and in the sequence of combinationsand process steps, as well as in other aspects of the inventiondiscussed herein, without departing from the scope of the invention

1. A gas fired infrared radiation emitter comprising a frame, a screenassembly attached to said frame, and a means for locking said screenassembly to said frame, wherein said screen assembly comprises a supportrod structure, at least four attachment rings and a screen, wherein saidattachment rings are disposed about said support rod structure and areadapted to secure said screen to said support rod structure, wherein:(a) said support rod structure is comprised of a first outerlongitudinal support rod, a second outer longitudinal support rod, afirst inner longitudinal support rod, and a second inner longitudinalsupport rod, wherein:
 1. each of said first and second outerlongitudinal support rods, and each of said first and second innerlongitudinal support rods, are substantially parallel to each other;forming an angle with regard to each other of from about 0 to about 5degrees;
 2. said first outer longitudinal support rod is connected tosaid first inner longitudinal support rod, and
 3. said second outerlongitudinal support rod is connected to said second inner longitudinalsupport rod,
 4. said first inner longitudinal support rod is connectedto said second inner longitudinal support rod; (b) each of saidattachment rings is contiguous with a portion of said screen and, at thepoint at which each such attachment ring is contiguous with said screen,forms a screen contact point; and (c) the distance between any onescreen contact point and the next closest screen contact point does notexceed 75 millimeters.
 2. The gas fired radiation emitter as recited inclaim 1, wherein said screen assembly is removably attached to saidframe.
 3. The gas fired radiation emitter as recited in claim 2, whereinsaid radiation emitter is comprised of means for releasably locking saidscreen assembly to said frame.
 4. The gas fired radiation emitter asrecited in claim 2, wherein said support rod structure comprises a firstmember, a second member, a third member, a fourth member and a fifthmember, and wherein said second member, said third member and saidfourth member form a substantially H shaped connecting portion.
 5. Thegas fired radiation emitter as recited in claim 4, wherein saidradiation emitter is comprised of at least 10 of said attachment rings.6. The gas fired radiation emitter as recited in claim 4, wherein saidradiation emitter is comprised of from about 4 to about 16 of saidattachment rings.
 7. The gas fired infrared radiation emitter of claim1, wherein said frame comprises a first side, a second side, a firstend, and a second end, wherein said first side of said frame isintegrally connected to a first screen support, said second side of saidframe is integrally connected to a second screen support, and saidscreen assembly is contiguous with said first screen support and saidsecond screen support.
 8. The gas fired infrared radiation emitter ofclaim 7, wherein said first end of said frame is integrally connected toa first vertically extending mounting bracket and a second verticallyextending mounting bracket, wherein said second end of said frame isintegrally connected to a third vertically extending mounting bracketand a fourth vertically extending mounting bracket, and wherein saidfirst vertically extending mounting bracket, said second verticallyextending mounting bracket, said third vertically extending mountingbracket and said fourth vertically extending mounting bracket areadapted to engage said screen assembly.
 9. The gas fired infraredradiation emitter of claim 8, wherein said first vertically extendingmounting bracket comprises a first orifice adapted to receive one ofsaid first member or said fifth member, said second vertically extendingmounting bracket comprises a second orifice adapted to receive one ofsaid first member or said fifth member, said third vertically extendingmounting bracket comprises a third orifice adapted to receive one ofsaid first member or said fifth member, said fourth vertically extendingmounting bracket comprises a fourth orifice adapted to receive one ofsaid first member or said fifth member.
 10. The gas fired infraredradiation emitter of claim 9, wherein said emitter further comprises ameans for allowing movement of said first member and said fifth membertowards one of said first end of said frame or said second end of saidframe.
 11. The gas fired infrared radiation emitter of claim 10, whereinsaid emitter further comprises a means for limiting the movement of saidfirst member and said fifth member towards one of said first side ofsaid frame and said second side of said frame.
 12. The gas firedinfrared radiation emitter of claim 11, wherein said frame furthercomprises an upper surface, wherein said first vertically extendingmounting bracket, said second vertically extending mounting bracket,said third vertically extending mounting bracket and said fourthvertically extending mounting bracket form an angle with said uppersurface of said frame of from about 70 to about 90 degrees.
 13. The gasfired infrared radiation emitter of claim 12, wherein said firstvertically extending mounting bracket, said second vertically extendingmounting bracket, said third vertically extending mounting bracket andsaid fourth vertically extending mounting bracket have a height of fromabout 8 millimeters to about 20 millimeters.
 14. The gas fired infraredradiation emitter of claim 13, wherein said first vertically extendingmounting bracket comprises a fifth orifice adapted to receive a lockingdevice, said second vertically extending mounting bracket comprises asixth orifice adapted to receive a locking device, said third verticallyextending mounting bracket comprises a seventh orifice adapted toreceive a locking device, and said fourth vertically extending mountingbracket comprises an eighth orifice adapted to receive a locking device.15. The gas fired infrared radiation emitter of claim 14, wherein saidfirst orifice, said second orifice, said third orifice, and said fourthorifice comprise a slot-type opening disposed at a distance of fromabout 7 millimeters to about 14 millimeters from said upper surface ofsaid frame.
 16. The gas fired infrared radiation emitter of claim 15,wherein said first screen support further comprises a first top surface,said second screen support further comprises a second top surface, saidfirst screen support and said second screen support further comprise aheight of from about 7 millimeters to about 14 millimeters, and saidfirst top surface of said first screen support and said second topsurface of said second screen support comprise a height that issubstantially the same distance as said distance said slot-type openingis disposed from said upper surface of said frame.
 17. The gas firedinfrared radiation emitter of claim 16, wherein said first membercomprises a first securing point and a second securing point, said fifthmember comprises a third securing point and a fourth securing point,wherein said first securing point and said second securing point eachcomprise a bend in opposing ends of said first member where said bendscomprise a radius of from about 45 to about 330 degrees and wherein saidthird securing point and said fourth securing point each comprise a bendin opposing ends of said second member where said bends comprise aradius of from about 45 to about 330 degrees.
 18. The gas fired infraredradiation emitter of claim 17, wherein said screen comprises a length offrom about 2 to about 20 inches and a width of from about 1 to about 10inches.
 19. The gas fired infrared radiation emitter of claim 18,wherein said screen further comprises an open space area of from about30 to about 70 percent of the total surface area of said screen.
 20. Thegas fired infrared radiation emitter of claim 19, wherein the length ofsaid first member and said fifth member comprise from about 1.5 to about25 inches.